Improvement in the methods of blasting rock



I. WHITCUMB Methods of Blasting Rocks.

Patented July 29,1873.

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aZzu/ AM PHOTO-UTHUGRAIIIIC ca MK (oseomvs macsss) UNITED STATES PATENTQFFICE,

ISRAEL WHITCOMB, OF HINGHAM, MASSACHUSETTS.

IMPROVEMENT IN THE METHODS OF BLASTING ROCK.

Specification forming part of Letters Patent No. 141,248, dated July 29,1873; application filed May 21, 1873.

To all whom it may concern:

Be it known that I, ISRAEL WHITCOMB, of Hingham, of the county ofPlymouth, of the State of Massachusetts, have invented a new and usefulImprovement in the Art of Blasting Stone; and do hereby declare the sameto be fully described, as follows, reference being had to theaccompanying drawings, of Wl1lCll- Figure 1 is a top View of ablast-hole and its diametric partition. Fig. 2 is a vertical andtransverse section of it. Fig. 3 is a side view of one of thepartitions; and Figs. 4 and 5 are side views, and Fig. 6 an end view, ofthe implement used for introducing the partition into and properlycentering it in a blast-hole.

In' carrying out my invention or improvement in the art of blasting, orin the preparation and charging of a hole made in arock or stone for thepurpose of blasting it, I introduce into the hole, so as to extendacross it diametrically, and from its bottom upward to or nearly to itstop, a partition, generally of wood, a common lath as used by plasterersbeing what I have mostly employed. The blasting'charge, whether ofgunpowder, gun-cotton, or other suitable material, is next to beintroduced into the hole, so as to either partially or entirely fill thespaces on opposite sides of the partition. Furthermore, the partition,in order for efi'ecting the best result, should fit closely at itsopposite edges to the hole.

In the drawings, A denotes a blast-hole drilled in a stone, B, andhaving the wooden partition 0 arranged in it. For introducing thepartition into a hole, I generally employ a furcated metallic cylinderor rod, D, provided with a handle, E, all as shown in Figs. 4, 5, and 6,which is an end View of the rod. Such rod has a diameter a little lessthan that of the blast-hole,and is slotted diametrically from its lowerend upward the necessary length, as seen at a, to receive the partition,the axis of the handle and the planes of the opposite sides of the slotbeing in parallel planes. Having placed in the slot one of thepartitions, the rod with it is to be introduced into and pushed downwithin the blast-hole, until the end of the partition may reach thebottom of the hole. On withdrawal of the rod from the hole, thepartition will remain in the hole, and be duly centralized therein.

I have discovered that by the use of the partition, the stone may beblasted or cracked in any direction diametrically of the hole that maybe desirable. To insure such, it is only necessary to turn or set thepartition in the hole so that the line of greatest width of thepartition shall be in the direction in which we may desire the rock orstone to split.

By placing the handle of the partition-adjuster in the prepareddirection of fracture, the partition when in the hole and the ad justerwill have the proper position for insuring the required line of crack orcleavage.

With a series of blast-holes prepared with partitions and blast-charges,a stone may be split either in a straight or in a curved or irregularline, as may be desirable.

When the partition is used in a blast-hole, the charge of powder willextend much higher in the hole than would be the case without thepartition, and as a consequence the force of the explosion will bespread to a greater extent, and be caused to act mostly in oppositedirections, or at right angles to the line of rupture, the partitionpreventing to a great degree, if not entirely, the force of the chargebeing exerted in range of the partition.

I sometimes put two partitions in a hole,

with a powder-space between them, and with such spaces on their outersides, or I put two wooden partitions or segments of cylinders in thehole, with their cord-planes parallel and apart, so as to have a powderor charge space between them; but such, though advantageous, is not somuch so as the single partition arranged diametrically across the hole.a In the preparation of a cartridge for blasting purposes, I place thepartition within the case of such cartridge having the powder on opposite sides of such partition. I deem it far better, however, to .firstdrive the partition into the blast-hole by means of the adjuster, asdescribed, and afterward place the powdercharge in the hole.

Instead of the hole being cylindrical it may have the shape inhorizontal section of a Lewis hole, or be longer in width in onedirection than it may be in one at right angles,

the partition being placed to extend along the What, therefore, I claimas my invention or longer diameter of the hole. improvement in the artof blasting, is-

By the use of a partition in manner as de- The employment of one or morepartitions scribed, with a blast-hole and its explosive or pieces ofwood, with or in a blast-hole, and charge, highly important advantagesare with its explosive charge,all substantially in gained in blasting.manner as specified.

It will be seen that when the charge in op- ISRAEL WHITOOMB. positesides of the partition is exploded it will compress the wood, wherebythe partition will Witnesses be expanded so as to cause it at its edgesto R. H. EDDY, fit closely to the stone. J. R. SNOW.

